“This is 1 of the best TTS and its smooth. If this is truly free i'll keep this 100%. Every other TTS says its free but has a secret. They interrupt or they just say better ai voices pay. But i like this voice. I've tried loads and this is 1 of the best ones that actually says free.”
Hear Your Google Doc Out Loud — Catch Typos Your Eyes Miss
Turn any Google Doc into audio. Open it in Chrome, click CastReader, and listen to your documents with natural AI voices.
Project Proposal: AI Integration
This proposal outlines our plan to integrate artificial intelligence capabilities into the existing workflow management system. The implementation will proceed in three phases over the next six months.
Phase one focuses on natural language processing for automated task categorization. By analyzing task descriptions, the system will automatically assign priority levels and route items to appropriate team members.
Reads Google Docs aloud — word-by-word highlighting follows along
Why Listen to Google Docs with CastReader?
Review documents without reading a single word
One Click
Read Any Document Aloud
Open any Google Doc, click the CastReader icon, and it reads the entire document with natural AI voices. No copy-paste needed.
Better Than Built-in
Natural AI Voices
Google Docs has basic accessibility TTS, but CastReader's Kokoro AI model sounds significantly more natural and expressive.
Follow Along
Paragraph Highlighting
CastReader highlights the current paragraph and auto-scrolls through your document. Click any paragraph to jump there.
100% Free
No Limits, No Account
Completely free. No signup, no limits, no subscription. Just install and start listening.
Frequently Asked Questions
Everything you need to know about listening to content with CastReader
How do I listen to a Google Doc?
Install CastReader from the Chrome Web Store, open your Google Doc in Chrome, and click the CastReader icon. It reads the document aloud with AI voices.
Is this better than Google Docs' built-in TTS?
Yes. Google Docs' accessibility tools use basic browser TTS voices. CastReader uses the Kokoro AI model which sounds significantly more natural and human-like.
Does it work with Google Slides or Sheets?
CastReader works best with text-heavy Google Docs. Slides and Sheets have limited text extraction support.
Is it free?
Completely free with no limits. No signup required.
Can I adjust the speed?
Yes. Use the floating player to speed up or slow down playback.
Does it highlight text as it reads?
Yes. The current paragraph is highlighted and the page auto-scrolls to follow along.
Does it work with shared Google Docs?
Yes. Any Google Doc you can view in your browser can be read aloud.
What about Google Docs in other languages?
CastReader supports 40+ languages with natural AI voices.
Why TTS Matters in 2026
Hard numbers — not vibes — from authoritative sources
$2.22 billion
US audiobook sales in 2024, up 13% year-over-year (Publishers Weekly / Audio Publishers Association)
Source →51%
of US adults have listened to an audiobook in 2025 — roughly 134 million people (APA Consumer Survey 2025)
Source →2.2 billion
people globally with near- or far-vision impairment (WHO Fact Sheet, 2024). TTS is the primary access path for digital reading content.
Source →78%
of audiobook listeners multitask while listening — commute, chores, exercise (Audiolibrix Great Audiobook Survey, 2024)
Source →27.2 minutes
average single-trip US commute in 2024, up from 26.8 (US Census ACS via Statista). That's nearly an hour each day of audio-only time.
Source →effect size 0.35
measured comprehension lift from TTS for reading-disabled students across 22 studies (Wood, Moxley, Tighe & Wagner, Journal of Learning Disabilities, 2018)
Source →15.5 million
US adults with ADHD per CDC 2024 — about half diagnosed in adulthood (CDC MMWR, October 2024)
Source →What Readers Say — Including the Critical Reviews
Every Chrome Web Store review below is verifiable at the link in each card. We don't hide negative feedback — we answer it within 24 hours.
“Works perfectly on vivaldi. One suggestion though. I wish it had a play button appear next to a paragraph when we hover over it. Just like in the case of speechify.”
“Extremely user friendly short keys. Placed forward backward and speed up down as Natural as it could be. Voices are great and smooth. I would recommend it over many hyped products.”
“At the very least it's better than many paid TTS models. Still not as good as ElevenReader or LAP, but maybe the best free model for TTS.”
“So glad I can finally switch voices! The default was fine but I found one I actually enjoy listening to for hours. Small thing, huge difference.”
“Best one i found, user friendly, and great voice over.”
“ChatGPT's long answers are finally listenable. Let it generate while I listen — doubles my productivity. Love the inline button next to each response.”
“I tried using this add-on to listen to an ebook on the O'Reilly learning platform, and it works smoothly. However, it always restarts from the first paragraph whenever I scroll or select a different paragraph. Please consider adding a bookmark or checkpoint feature so users can mark where the reading should begin.”
↪ Founder reply
Replied by CastReader founder Yan Xu within 48 hours: acknowledged the issue, shipped a bookmark feature in the following release. Reviewer's verbatim feedback drove the v1.2 roadmap.
“Need to highlight text and select it.”
“Hard to select text.”
↪ Founder reply
Replied by CastReader founder Yan Xu within 24 hours: apologized, asked which site/browser the issue occurred on, provided a workaround using the keyboard shortcut, and offered direct support at support@castreader.ai.
Recent Updates
We re-test, re-write, and ship continuously. Every entry has a real date.
Site-wide trust signals refresh
Rewrote landing pages with verbatim Chrome Web Store testimonials, real audiobook market data, and tested-12-extensions methodology. Every claim now has a sourceable link.
Send-to-Phone reliability improvements
Telegram audio streaming now auto-turns pages reliably across Kindle Cloud Reader and Apple Books. Reduces session interruptions by ~70% in internal testing.
Technical deep-dive published
Wrote up the OCR pipeline: how CastReader handles Amazon's 184 random font alphabets and 361 unique glyphs per Kindle book. Shared in dev.to.
CastReader for Mac released
Native macOS app reads Kindle for Mac with word-level highlighting. Floating player + system-wide hotkeys. No browser needed.
Featured on Product Hunt
Ranked #10 in Daily, 99 upvotes, 4 community comments shaped the v1.2 roadmap.
Voice quality upgrade — Kokoro AI
Switched from older TTS engines to Kokoro neural voices. User reviews shifted from 'usable but robotic' to 'enjoy listening for hours' (verbatim from review by patrick chiang).
First wave of extraction reliability improvements
OCR success rate improved from 78% to 89% on English-language Kindle books. Multi-column page detection added for academic PDFs.
Why This Exists
I built CastReader because I owned hundreds of Kindle books and couldn't listen to them on my morning runs without buying separate Audible copies. The technical problem — Amazon's Cloud Reader font encryption — turned out to be solvable with OCR. The product problem — making it actually pleasant across phones, desktops, and 40+ languages — took two years of iteration. We're a small team. I answer every Chrome Web Store review personally (see testimonials above — including the 3-star and 1-star ones). If something's broken or missing, email support@castreader.ai.
— Yan Xu, founder
Last reviewed: · CastReader Team — reviewed against 2025 testing data
Start Listening Now
Completely free. No signup. No limits. Install and start listening.
★★★★★ 4.7 · Free · No login · No limits